Advice on muzzleloader - not the "usual" options

[Bosteldr]

Had a similar issue with range accuracy. I stopped using patch lube and used only spit patch for round ball shooting. Cut my group in half beyond 50 yds. Seems the patch lube is too slick and the round ball was not stable inflight.

 

[Billnpatti]

Some of the barrels for plains rifles are made to shoot conicals since many hunters seem to think that they need conicals for hunting. The conicals require a faster twist rate so if you have a barrel that was made to shoot modern conicals it is unlikely that it will ever shoot patched round balls worth a darn. The twist rate is just too fast for a round ball. Determine your twist rate and if is much faster than 1:48, it is a conical barrel. If it has a twist rate of 1:48 or slower (the higher the number, the slower the twist rate), say 1:66 or so, then it is a round ball barrel and using Dutch Schoultz' Black powder Accuracy System http://www.blackpowderrifleaccuracy.com/ will have you cutting Xs with it. You must do exactly what he says and in the order that he tells you if you are to get the maximum benefit from it. But, I can tell you this, it works. Plain and simple....it works and it is worth every penny.

 

[Snakebite]

Bill, back when I started shooting BP in the 70s, it seemed like all the RB barrels were 1:60 or slower and TC Hawken was 1:48 for Maxi-Balls. Even today, it seems like any of the larger RBs (.45 and up) are the slower twist, but .40cal it seems like the optimum twist is 1:48. I'm assuming it's all due to the size of the ball. I've never really researched a .32 or .36cal long gun but am assuming they are also the 1:48 twist range.

What are your thought?

Snakebite

 

[Billnpatti]

Well, you've got me on a spot because I can't remember what specific barrels were made for conicals. I think the T/C Big Boar was a fast twist rate barrel designed specifically for conicals. I have heard of some of the after market large bore barrels being made with a twist rate faster than 1:48 but I can't tell you which ones. I do know that the 1:48 twist rate barrels will not shoot the sabot bullets worth a darn. A friend of mine gave me some sabot bullets several years ago and I tried them in my T/C Hawken and I would have been better off just throwing them. Another thing that wouldn't work in the 1:48 teist rate barrel was a device that didn't last long on the market was the PolyPatch. Not only couldn't I get a group with them, I couldn't even get a pattern. I think everyone found that they were a bust.

But, back to your original question, I am sure that there after market barrels out there that are drop ins for some of the plains rifles that are made specifically for the sabot bullets but I can't tell exactly who made/makes them.

 

[Snakebite]

Bill,

Didn't mean to put you on the spot. I guess the direct question would be why do .40cal round ball barrels tend to be 1:48 rather than a slower twist?

Chris

 

[Billnpatti]

Hmmmmmm :hmm: I don't have the answer for that one either. I know that there were a lot of barrels in the smaller calibers that had pretty slow twists. I have a .36 with a 1:66 twist that seems to shoot pretty well. But if I were to attempt a SWAG, I'd say that it was because the larger masses of the balls for the large bores take more time to overcome their inertia start rotating and would, therefore, require a slower twist while the smaller masses of the smaller caliber balls overcome their inertia more easily and will work with a faster rate of twist. You want as fast a rate of rotation as possible because the faster it rotates, the more stability it has in flight. This rotation is the whole purpose of rifling.

I'm going to take a look in my Ballistics book and see if it says anything about these rates of twist with respect to caliber for a round ball. I know it addresses rates of twist for conicals as a function of projectile aspect ratio and velocity but I don't know if it addresses twist rates for patched roundballs. :idunno:

It would seem that the 1:48 has proven to be a pretty good overall rate of twist in many, if not all, calibers. From what I have read, almost all Hawken rifles have the 1:48 rate of twist. It seems that most of them were made in the larger calibers (= or >.50). Again, I must say :idunno:

 

[Col. Batguano]

the formula for optimum twist of a PRB (that's the minimum weight by caliber is usually around 1.25 x caliber. It's a more complicated foumula than that, but it's at least a decent guideline. You need faster twist rates to stabilize heavier projectiles. That's part of the reason why most .22 rf rifles are 1:16, and .22 centerfires are faster, like 1:9